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Based on the material removal model, it was concluded that the increase of finishing pressure was a practicable method for improving the efficiency of the magnetic abrasive finishing. By adding ultrasonic vibration to the magnetic abrasive finishing process, the instantaneous pulsating finishing pressure of magnetic abrasive particles could be increased. Experiment results showed that, magnetic abrasive particles could efficiently remove the workpiece material and keep surface smooth with the combined force in rotational movement and vertical impact. The practical experiment proved that the finishing efficiency was improved by 50% or so. The surface roughness of workpiece decreased to 0.06μm. Compared with only magnetic abrasive finishing, the ultrasonic vibration-assisted magnetic abrasive finishing made the surface morphology smoother and well-distributed in digital microscope. By using X-ray interferometer detection, the stress state of workpiece surface layer after ultrasonic vibration-assisted magnetic abrasive finishing changed from residual tensile stress (+320 MPa) to compressed stress (-40 MPa), which effectively improved fatigue strength of workpiece. 